package chapter10.demo01;
import java.sql.*;
import java.util.Scanner;

public class demo01 {
    public static void main(String[] args) throws SQLException{
        //修改用户名和密码
        /*
        * 1.注册驱动
        * 2.获取连接
        * 3.创建(表结构)Statement对象
        * 4.执行SQL语句
        * 5.操作返回结果
        * 6.关闭连接
        */
        Statement stmt = null;
        ResultSet rs = null;
        Connection conn = null;
        try {
            Class.forName("com.mysql.cj.jdbc.Driver");
            String url = "jdbc:mysql://localhost:3306/jdbc?serverTimezone=GMT%2b8&useSSL=false";
            String username = "root";//数据库账户
            String password = "0324love502";
            conn = DriverManager.getConnection(url, username, password);
            /*
             * 静态sql语句用Statement
             * 动态sql语句用PreparedStatement
             * */
            Scanner sc = new Scanner(System.in);
            System.out.println("请输入你的旧账号名");
            String n1 = sc.next();
            System.out.println("请输入你的旧密码");
            String p1 = sc.next();
            System.out.println("请输入你的新账号名");
            String n2 = sc.next();
            System.out.println("请输入你的新密码");
            String p2 = sc.next();
            String updateSQL = "update users set name=?,password=? where name=? and password=?";
            PreparedStatement ps = conn.prepareStatement(updateSQL);
            ps.setString(1, n2);
            ps.setString(2, p2);
            ps.setString(3, n1);
            ps.setString(4, p1);
            int res = ps.executeUpdate();
            System.out.println(res);
            if (res > 0) {
                System.out.println("账号密码更新成功");
            } else {
                System.out.println("账号密码更新失败");
            }
        }catch (ClassNotFoundException e){
            e.printStackTrace();
        }finally{
            //6.回收数据资源
            if (rs !=null){
                try{
                    rs.close();
                }catch(SQLException e){
                    e.printStackTrace();
                }
                rs = null;
            }
            if (stmt != null){
                try{
                    stmt.close();
                }catch (SQLException e){
                    e.printStackTrace();
                }
            }stmt =null;
        }
        if(conn !=null){
            try{
                conn.close();
            }catch (SQLException e){
                e.printStackTrace();
            }conn = null;
        }
    }
}
